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A new species of hagfish, Eptatretus albiderma sp. nov. (Agnatha: Myxinidae), from Vietnam, with the keys to species of Eptatretus in East Asia


The whitish hagfish, Eptatretus albiderma sp. nov., was collected from the northeast Sea of Vietnam (Da Nang). This new species possesses six pairs of gill apertures, three multicusps, 18–21 prebranchial slime pores, absent or one branchial slime pore, and whitish to pinkish body color. Eptatretus albiderma sp. nov. can be readily distinguished from Eptatretus atami (Dean, 1904) and Eptatretus sheni (Kuo, Huang & Mok, 1994) by the numbers of total cusps (41–43 vs. 47–52 in E. atami vs. 48–53 in E. sheni), body color (whitish vs. darkish in E. atami vs. dark brown dorsally, lighter ventrally in E. sheni), eyespots (absent or faint vs. prominent in E. sheni), and total slime pores (74–78 vs. 71–78 in E. atami vs. 62–74 in E. sheni). The new species is clearly distinguished from E. atami by 0.026 pairwise genetic distance (d) of phylogeny based on mtDNA COI. We herein offer the key to 17 species of the genus Eptatretus Cloquet, 1819 in East Asia.

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We sincerely thank for David Catania (California Academy of Sciences, CAS), Hsuan-Ching Ho (National Museum of Marine Biology and Aquarium, NMMB), Shih-Pin Huang (Academia Sinica, ASIZP) for the loan of specimens and assistance with measurements, and Hin-Kiu Mok on the comments and Yoshiaki Kai (Kyoto University, FAKU) for the loan of specimens. We also thank for the valuable comments of reviewers to improve the paper.


This research was supported by the Marine Biotechnology Program of the Korea Institute of Marine Science and Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (MOF) (No. 20170431).

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Conceptualization, design, experiments, writing of research: YSS JKK.

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Correspondence to Jin-Koo Kim.

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Communicated by R. Thiel

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Song, Y.S., Kim, JK. A new species of hagfish, Eptatretus albiderma sp. nov. (Agnatha: Myxinidae), from Vietnam, with the keys to species of Eptatretus in East Asia. Mar. Biodivers. 50, 71 (2020).

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  • Mitochondrial DNA
  • Morphology
  • Vietnam
  • Myxiniformes
  • Taxonomy